Conquering the Integral of (1/x)*exp(-ax^2): A Scientific Inquiry

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Homework Statement
Essentially - find <1/x>, i.e. the mean of 1/x. The distribution probability density is of the form exp(-ax^2).
Relevant Equations
Mean of G = integrate ( G f(x) ) dx
Hopeless. I tried to use Taylor expansion but the zeroes and infinities go out of control really quick.
I tried WolframAlpha and it gave a special function.
What integrating trick am I missing? Or is it nonsense to solve it simply by hand?
 
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The expectation value is infinite.
 
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Orodruin said:
The expectation value is infinite.
Ah I'm so stupid. Thank you. Also another reality check for me.
 
<1/x>=0 as 1/x is an odd function and G*f(x) is then also odd.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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